One method for evaluating the knowledge or skill of a person such as a student includes the use of standardized tests. Some tests include questions that are answered by filling in an appropriate oval in an associated bubble-type answer sheet. Some standardized tests include open-ended questions for which the answers to those questions are evaluated and scored by a human reviewer or a computer, also referred to herein as a reader. Some test-takers write answers outside of a scanned answer area, and some handwritten answers are difficult to read and process.
FIG. 1 illustrates one example of an answer sheet 100 for a standardized test. A section answer area 102 is used to answer multiple choice questions for a section of questions, and each multiple choice question is associated with a specific question answer area 104. Some test-takers unintentionally enter their answer at the incorrect location or wrong line on the answer sheet.
Known image scanners for processing large numbers of forms, such as standardized test answer sheets, drop out at least part of the visible spectrum (e.g. certain color(s)). For example, test-takers have been required to use a pencil such that the answer markings are capable of being detected by a dropout scanner. The ovals and the lettering are printed with a dropout background color so that the background does not interfere with detecting the answer markings. FIG. 2 illustrates one example of a scanned image of the answer sheet of FIG. 1 when the answer sheet 200 is marked with markings (such as a pencil or some black inks) which are detected by the scanner. However, some test-takers mark their answers using a color ink pen or other writing utensil that is not detected by the scanner. For example, some systems do not recognize blue, red or green ink. FIG. 3 illustrates one example of an image of the answer sheet of FIG. 1 when the markings on the answer sheet 300 are not detected. The resulting image is not able to be scored as it does not contain answer markings.
The illustrated answer sheet 100 of FIG. 1 also includes registration marks such as corner fiducials 106 and row fiducials 108 that can be detected by the dropout scanner. The fiducials are used to accurately position or register the answer sheet (without the dropped out background color) allowing the detected answer markings to be accurately scored. However, the detectable fiducial markings and the dropout background color are printed using different print stations, which can introduce a print registration error between the printed fiducial markings and background color. Scoring errors result when the print registration errors are large enough to cause an improper association between the answer and the answer choices.
Therefore, there is a need in the art to provide improved systems and methods for processing forms such as standardized tests.